Myelin is a multilamellar membrane, which provides electrical insulation around the axon and participates to bidirectional communication with neurons and the extracellular environment. In glial cells, myelin biogenesis involves sorting and recruitment of selected lipids, proteins, and mRNAs to specific sub-domains, with a strong analogy to polarized transport in epithelial cells and neuronal synapses. However, the molecular basis for sorting and polarized transport in Schwann cells and oligodendrocytes are largely unknown. The focus of our laboratory is to elucidate the molecular mechanisms that regulate membrane trafficking and homeostasis during myelin biogenesis and how defects of this process provoke human diseases.